The Evolved Packet Core (EPC) is the core network of advanced mobile communication systems. The EPC allows different radio access technologies (RATs) to operate in an integrated manner. These radio access technologies include first generation wireless Local Area Networks (LANs), second generation (2G) systems, such as Global System for Mobile communication, or GSM, third generation systems, such as the Universal Mobile Telecommunication System (UMTS), and fourth generation systems, such as Long Term Evolution (LTE).
Under LTE, a User Equipment (UE) connects to the EPC over the LTE access network known as E-UTRAN (short for Evolved UMTS Terrestrial Radio Access Network) and communicates with a base station known as the Evolved NodeB (eNB). The EPC is a packet-switched network in which the Internet Protocol is used for all transport services. The EPC is part of the 3rd Generation Partnership Project (3GPP) specification.
Multiple-input-multiple-output (MIMO) under LTE exploits multiple antennas at both the UE and the eNB to improve the robustness of data transmissions (transmit diversity) and/or the data rate (spatial multiplexing). Along with MIMO, beamforming is a technique used in LTE to improve signal transmission between the eNB and the UE. Instead of broadcasting a signal to a wide area, the eNB aims the signal toward the UE. One way to achieve this is by separating the signal to be transmitted into an array of separate antenna signals and then weighting the magnitude and phase of each signal. An improvement of the received signal under this technique is known as a beamforming gain.
Starting with Release 8 of the 3GPP specification, MIMO has been supported and is found in many LTE cellular systems. However, as recently as Releases 10 and 12, the MIMO enhancements were designed to support antenna configurations at the eNB that are capable of adaptation in the azimuth only.
Thus, there is desired a system design to overcome the shortcomings of the prior art.